Course conditions | WINTER 2011/12
Creeping bentgrass cultivars affected We originally isolated Aaa from Penn G-2 creeping bentgrass. We have since found it in other creeping bentgrass cultivars samples from other golf course that were sent to our laboratory. We have also inoculated several creeping bentgrass cultivars in growth chambers. These cultivars include, but are not limited to: Penn A-4, Penn A-1, L-93, Tyee, Declaration, Bengal, 007, and Penncross. Our initial research has indicated some minor variations in susceptibility in growth chamber inoculations; however, all cultivars tested thus far have been susceptible to infection by Aaa, to some degree.
What still needs to be done There seems to be a movement in Michigan towards converting annual bluegrass greens to creeping bentgrass greens. Additionally, many of the new golf courses that were built in the last ten years are still predominately creeping bentgrass. Much still remains to be learned about the Acidovorax turfgrass pathogen, we are working to understand many aspects of the disease. It is important that we find a means of controlling this disease and its associated symptoms. We began trials last season, but without much success. We will continue them this year with the hope of obtaining better results. Stay tuned in to MSU research reports and industry publications for progress that is being made on this emerging issue. IMicroscopic view of bacterial cells flowing out of the cut end of an infected turfgrass plant. A common diagnostic sign of bacterial infection byXanthomonas (poa annua) or Acidovorax (creeping bentgrass).
Irregular shaped area of seeded creeping bentgrass etiolating due to infection by the bacterium Acidovorax avenae subsp. avenae.
TURF & ORNAMENTAL PRODUCTS
Jim Kruger Technical Sales Representative 517-719-0323 Jim.Kruger@clearychemical.net www.clearychemical.com
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